Arrangement for the measurement oef large volumes of water for water turbines



ARRANGEMENT FOR THE MEASUREMENT OF LARGE VQLIIJMES OF WATER FOR WATER TURBINES i l March 26, 1929. w. E. GERMER 1,706,848 I Filed May 3. 1922 Mines-59s: v Inventor: W M 5 wdwa4d 0220/ PATENT OFFICE.

WKLEEIJM EDUARD GERMEB, OF BEBLIN-CHARLOTTENBURG, GERMANY.

NGEH ENT FOR THE MEASUREMENT OF LARGE VOLUMES OFWATER FOR WATER TUBBINES.

Application filed May 3, 1922, Serial No. 558,216, and in Germany May 6, 1921.

The supervision of the efiiciency of water turbines requires an exact determination of the water which is used for each individual unit. The pressure pipe lines have generally a comparatively large diameter, so that only measuring instruments for closed conduits can be used. The measurement with the Pitot tube is tedious, and requires special practice when exact measurements shall he obtained. In most cases the water used by the turbine has been measured by means of an overflow weir inserted in the discharge channel. This method of measurement is however not suitable for carrying out a continuous supervision of the plant. The insertion of Venturi meters such as has already been carried out in some instances in larger plants does not find the approval or the hydraulic engineers because the loss of head caused by the insertion of a Venturi meter destroys too great a part of the available power. in hydro-electrical plants the measurement of the water used becomes too onpensive as the continuous loss of electrical energy connected therewith is too great.

The measurement of water by means of a Venturi apparatus causes at the narrowest part of the Venturi tube (lthe throat) a considerable increase of the ve ocity of the water.

This increase in velocity takes lace without nearly any loss of head. A loss 1s 0111 caused in the ex aniline; cone of the tube w iere the increase velocity of the water used for measuring purposes is again converted into static pressure. At the end of the high pressure conduit the static water pressure is then finally converted into velocity so as to yield its entire kinetic energy to the turbine wheel.

Now the object of the present invention is to avoid as much as possible for measuring purposes the loss of head due to the insertion of a Venturi meter. Keepin in mind that for the utilization of the kinetic energy in the water a conversion is necessary of the static pressure into velocity and considering that in a Venturi meter the measurement is also obtained lay such a conversion it is possible to combine both efiects with the same conversion. As the said conversion of static pressure into velocity can be performed nearly without loss of head the measurement is made possible almost without a loss of power. In this arrangement it is not necessary to convert the velocity a ain into static pressure as is done in the or ina Vcnturi meter where it can onl be carric out with a certain loss of hen The figure oi the accompanying drawing shows dia rammatically one form of embodimentof lllS invention. The large turbine co conduit R is reduced in diameter immediate] y after entering the power house B and all that 1s necessary is to insert at this contracted part of the conduit a correctly shaped measurmg nozzle M. An increased velocity is thercc5 fore given to the water at this lace and will he still more increased at the c ischarge end of the conduit to obtain the required final velocity at the turbine wheel. As readilyseen a part of the velocitynecessary for the 7 production of. power is created for measuring purposes a short distance from the discharge end without it being necessary to reduce it again. The frictional loss due to the increase of velocity does not matter as the remaining part or the conduit is only short.

Thelarger side of nozzle M is connected lcy means of small pipe 0 with an indicating device such as for instance a ll-tuhe manometer D, the other side of the latter being connectcd by means of a small pipe E with the smaller side of nozzle M.

. Having now fully described .my invcn-' tion, what I claim and desire to secure by Letters Patent is:

The combination with a main water turbine conduit of a section for directly delivering the water to the turbine, said section having an opening of uniform diameter which is less than that of the main conduit, a pressure measuring device'and means causing the differential pressure produced in such reduction of diameter to act upon saic measuring device, substantially as and for the purpose set forth.

In testimony of which I have hereunto set my hand this 12th day of April A. D. 1922.

WILHEL M EDUARD GERMER. [L. 5.] 

